Reverse transmission apparatus

ABSTRACT

Disclosed herein is a reverse transmission apparatus, including: a gear assembly of a transmission; a driving input shaft configured to be connected to the gear assembly; and a sprag assembly configured to partially connect or cut off power of the gear assembly depending to a forward rotation or a reverse rotation of the driving input shaft so as to perform a shift operation, thereby freely performing a desired shift operation with a relatively simple configuration and a simple operation.

CROSS-REFERENCE(S) TO RELATED APPLICATIONS

This application claims priority to Korean Patent Application No(s).10-2013-0166376, filed on Dec. 30, 2013, which is incorporated herein byreference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Exemplary embodiments of the present invention relate to a reversetransmission apparatus, and more particularly, to a reverse transmissionapparatus capable of freely performing a desired shift operation with arelatively simple configuration and a simple operation.

2. Description of Related Art

Generally, a transmission of a vehicle is an apparatus which isinstalled between a clutch and a propeller shaft to increase or decreasea torque of an engine depending on a change in a driving state of thevehicle and enable the vehicle to be driven backward.

The typical transmission apparatus allows various shift mechanisms, suchas a synchromesh, to selectively connect or control power, therebyperforming a shift change.

Therefore, the typical transmission apparatus needs to include a shiftgear or a pulley and a shift operation mechanism so as to meet a desiredvelocity ratio, such that a configuration thereof may be complicated anda size thereof may be increased.

For this reason, a development of an apparatus which may perform adesired shift operation with a relatively simple configuration and asimple operation is urgently required.

RELATED ART DOCUMENT Patent Document

(Patent Document 0001) Korean U.M. Application No. 20-1996-0068263

SUMMARY OF THE INVENTION

An embodiment of the present invention is directed to a reversetransmission apparatus capable of freely performing a desired shiftoperation with a relatively simple configuration and a simple operation.

Other objects and advantages of the present invention can be understoodby the following description, and become apparent with reference to theembodiments of the present invention. Also, it is obvious to thoseskilled in the art to which the present invention pertains that theobjects and advantages of the present invention can be realized by themeans as claimed and combinations thereof.

In accordance with an embodiment of the present invention, a reversetransmission apparatus includes: a gear assembly of a transmission; adriving input shaft configured to be connected to the gear assembly; anda sprag assembly configured to partially connect or cut off power of thegear assembly depending to a forward rotation or a reverse rotation ofthe driving input shall so as to perform a shill operation.

The gear assembly may include: sun gears configured to be connected tothe driving input shaft; a plurality of planetary gears rotating,engaging with the sun gears; and ring gears configured to be internallygeared with the plurality of planetary gears, wherein the sprag assemblyis coupled with the sun gear and the ring gear, respectively, throughthe driving input shaft.

The sprag assembly may include: a first sprag configured to be mountedon the driving input shaft, coupled with the sun gear connected to thedriving input shaft, and restrict or unrestrict the rotation of the sungear depending on the forward rotation or the reverse rotation of thedriving input shaft; and a second sprag configured to be mounted on thedriving input shaft, coupled with the ring gears internally geared withthe plurality of planetary gears rotating, engaging with the sun gears,and restrict or unrestrict the rotation of the ring gear depending onthe forward rotation or the reverse rotation of the driving input shaft.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating the overall configuration of a reversetransmission apparatus according to an exemplary embodiment of thepresent invention.

FIG. 2 is a diagram viewed from viewpoint B of FIG. 1.

DESCRIPTION OF SPECIFIC EMBODIMENTS

Various advantages and features of the present invention and methodsaccomplishing thereof will become apparent from the followingdescription of embodiments with reference to the accompanying drawings.

However, the present invention is not limited to the exemplaryembodiments set forth herein, but may be embodied in many differentforms.

Rather, exemplary embodiments introduced herein are provided to makedisclosed contents thorough and complete and sufficiently transfer thespirit of the present invention to those skilled in the art.

In the drawings, a thickness of layers and regions are exaggerated forclarity.

The terms “upper end”, “lower end”, “upper surface”, “lower surface”,“upper portion”, “lower portion”, etc., are used to differentiaterelative positions of components.

For example, for convenience, when an upper side in the drawings refersto an upper portion and a lower side in the drawings refers to a lowerportion, actually, unless. deviating from the scope of the presentinvention, the upper may refer to the lower portion and the lowerportion may refer to the upper portion.

Terms used in the present specification are used only in order todescribe specific exemplary embodiments rather than limiting the presentinvention.

Singular forms are intended to include plural forms unless the contextclearly indicates otherwise.

It is to be understood that the terms “comprises” or “have” used in thisspecification specify the presence of stated features, steps,operations, components, parts mentioned in this specification, or acombination thereof; but do not preclude the presence or addition of oneor more other features, numerals, steps, operations, components, parts,or a combination thereof.

Unless defined otherwise, it is to be understood that all the terms usedin the specification including technical and scientific terms has thesame meaning as those that are understood by those who skilled in theart.

Generally, it is to be understood that the terms defined by thedictionary are identical with the meanings within the context of therelated art, and they should not be ideally or excessively formallydefined unless the context clearly dictates otherwise.

Hereinafter, exemplary embodiments of the present invention will bedescribed in detail with reference to the accompanying drawings.

FIG. 1 is a diagram illustrating the overall configuration of a reversetransmission apparatus according to an exemplary embodiment of thepresent invention and FIG. 2 is a diagram viewed from viewpoint B ofFIG. 1.

For reference, non-explained reference numeral 14 represents a planetarygear carrier, and in FIGS. 1 and 2, mark ‘{circle around ()}’represents a direction which approaches a reader from a ground viewed bythe reader and mark {circle around (x)} represents a direction which isaway from a reader from a ground viewed by the reader.

As illustrated, a reverse transmission apparatus according to anexemplary embodiment of the present invention may be configured toinclude a gear assembly 10, a driving input shaft 20, and a spragassembly 30.

The gear assembly 10 is embedded in a transmission and thus a shiftoperation is performed by a gear combination and the driving input shaft20 is connected to the gear assembly 10 to transfer a driving force tothe gear assembly 10. In this case, the transmission according to theexemplary embodiment of the present invention may be configured as avehicle transmission.

The sprag assembly 30 performs a shift operation by partially connectingor cutting off power of the gear assembly 10 depending on a forwardrotation or a reverse rotation of the driving input shaft 20.

Therefore, the reverse transmission apparatus according to the exemplaryembodiment of the present invention allows the sprag assembly 30 tosimply perform the shift operation by partially connecting or cuttingoff the power of the gear assembly 10 depending on only the forwardrotation or the reverse rotation of the driving input shaft 20, and doesnot require complicated and bulky parts like the transmission apparatusaccording to the related art.

The present invention may apply the foregoing exemplary embodiment andmay apply various exemplary embodiments to be described below.

The gear assembly 10 includes sun gears 11 which are connected to thedriving. input shaft 20, a plurality of planetary gears 12 rotating,engaging with the sun gears 11, and ring gears 13 which are internallygeared with the plurality of planetary gears 12.

Here, the sprag assembly 30 is coupled with the sun gear 11 and the ringgear 13, respectively, through the driving input shaft 20.

In this case, the sprag assembly 30 may be configured to include firstand second sprags 31 and 32.

The first sprag 31 is mounted on the driving input shaft 20, coupledwith the sun gear 11 which is connected to the driving input shaft 20,restricts or unrestricts the rotation of the sun gear 11 depending onthe forward rotation or the reverse rotation of the driving input shaft20.

The second sprag 32 is mounted on the driving input shaft 20, coupledwith the ring gears 13 which are integrally geared with the plurality ofplanetary gears 12 rotating, engaging with the sun gears 11, andrestricts or unrestricts the rotation of the ring gear 13 depending onthe forward rotation or the reverse rotation of the driving input shaft20.

The exemplary embodiment of the present invention illustrates anddescribes only the driving input shaft 20, but is not necessarilylimited to the configuration. Instead of the driving input shaft 20 asillustrated in FIG. 1, a member 20 as illustrated in FIG. 2 may also beapplied as the driving output shaft.

That is, as illustrated in FIG. 2, the driving output shaft 20 may beapplied as the case in which the driving output shaft 20 rotatesforwardly like {circle around (1)} to directly transfer a driving forceto the sun gear 11 or the case in which the driving output shaft 20rotate reversely like {circle around (2)} to be indirectly connected tothe ring gear 13 so as to forwardly rotate at a low speed.

In addition, the exemplary embodiment of the present invention is notparticularly illustrated, but in the reverse transmission apparatusaccording to the exemplary embodiment of the present invention isapplied, a reverse stage dog, clutch is applied and thus an apparatuswhich may perform forward and reverse shift operations may be applied.

That is, for a reverse movement, the dog clutch is applied to preventthe first sprag 31 or the second sprag 32 from being operated, and thusa rotation direction of an output stage may be adjusted to meet areverse shift operation.

Further, when the reverse transmission apparatus according to theexemplary embodiment of the present invention is applied to an outputstage sprag to perform a shift change in a slope road, and the like, thereverse transmission apparatus may also be used as a slip preventingapparatus which may prevent a vehicle from slipping.

Further, the exemplary embodiment of the present invention combines theforegoing reverse stage dog clutch with the slip preventing apparatus toselectively or simultaneously operate the reverse stage dog clutch andthe slip preventing apparatus, thereby expanding a driver's width ofselection.

That is, when the reverse stage dog clutch is released, the output stagesprag is operated simultaneously therewith or at a desired moment andwhen the reverse stage dog clutch is operated, a switching structure torelease the output stage sprag may be applied to prevent a mutualinterference between the slip prevention and the reverse apparatus.

In accordance with the exemplary embodiments of the present invention,the reverse transmission apparatus may perform the shift operation bysimply changing only the direction of the input shift so as to be usedfor various applications without the shift operation mechanism such asthe shift lever.

In particular, in accordance with the exemplary embodiments of thepresent invention, the reverse transmission apparatus may also beapplied to various fields such as an electric vehicle for which thedemand is expected to increase in future and thus may be considered tobe highly likely to be widely used.

Although the exemplary embodiments of the present invention have beendisclosed for illustrative purposes, those skilled in the art willappreciate that various modifications are possible, without departingfrom the scope and spirit of the invention as disclosed in theaccompanying claims

Accordingly, the scope of the present invention is not construed asbeing limited to the described embodiments but is defined by theappended claims as well as equivalents thereto.

What is claimed is:
 1. A reverse transmission apparatus, comprising: agear assembly of a transmission; a driving input shaft configured to beconnected to the gear assembly; and a sprag assembly configured topartially connect or cut off power of the gear assembly depending to aforward rotation or a reverse rotation of the driving input shaft so asto perform a shift operation.
 2. The reverse transmission apparatus ofclaim 1, wherein the gear assembly includes: sun gears configured to beconnected to the driving input shaft; a plurality of planetary gearsrotating, engaging with the sun gears; and ring gears configured to beinternally geared with the plurality of planetary gears, wherein thesprag assembly is coupled with the sun gear and the ring gear,respectively, through the driving input shaft.
 3. The reversetransmission apparatus of claim 1, wherein the sprag assembly includes:a first sprag configured to be mourned on the driving input shaft,coupled with the sun gear connected to the driving input shaft, andrestrict or unrestrict the rotation of the sun gear depending on theforward rotation or the reverse rotation of the driving input shaft; anda second sprag configured to be mounted on the driving input shaft,coupled with the ring gears internally geared with the plurality ofplanetary gears rotating, engaging with the sun gears, and restrict orunrestrict the rotation of the ring gear depending on the forwardrotation or the reverse rotation of the driving input shaft.